F-Zero GX for GameCube was one of a pair of games. It was released concurrently with F-Zero AX, a game designed for the Sega/Namco/Nintendo "Triforce" arcade platform, which connected to the home game via memory cards to unlock tracks. AX had arcade-style timed gameplay, along with those tracks.
Modder "Ralf" found that the full code for the arcade game is hidden on the GameCube disc – and accessible with a series of codes for the Action Replay cheat device. The long list of codes is found on The Cutting Room Floor (a site which, if this is your first visit, you're welcome).
Now, someone go peek in Mario Kart: Double Dash and see if Arcade GP is in there.